In the sentence below, should there be a 'that' after 'realized'? I was feeling really awkward about the construction here. I have put in the rest for context:

Someone commenting on an article about adulthood at xyz.com said that he realized he had made the 'official' transition to adulthood when as a 20 year old, he boarded his first flight without family or friends. 'I was on a plane headed to a different state, and no one cared', he noted.